An attacker armed with a knife killed three people inside a church Thursday in the Mediterranean city of Nice, French authorities said, prompting the country to raise its security alert status to the highest level.

Around half of the estimated 6,800 Yazidis taken captive are still missing. Women and girls from the minority who escaped described an organized system of slavery overseen by high-ranking foreign fighters.

The woman's killing in a public square was the cruelest moment in the descent of this once proud city.

Deep inside Syria, a bishop worked around the blurred edges of international law to save the lives of more than 200 people.

The network of agile and semiautonomous cells shows the reach of the extremist group in Europe even as it loses ground in Syria and Iraq.